British Astronomical Association
Supporting amateur astronomers since 1890

Secondary menu

Main menu

Home Forums Spectroscopy
Terms of use

A spectrum of HR Lyr

4 posts / 0 new
Last post
Robin Leadbeater's picture
Offline
Last seen: 3 hours 37 min ago
Joined: 05/03/2014 - 00:50
A spectrum of HR Lyr

I saw in October's Journal a report that HR Lyr (Nova Lyr 1919)   underwent a deep fade to mag 17 at the end of August (Shears and Poyner, observers notes p317) and a spectrum taken then showed strong emission lines (ATel 9418) so I thought I would take a look with my ALPY 200.

 Estimating the  brightness from the guider image gave mag 16.5 so it looks like it is on its way back to normal quiescence.

The spectrum shows a blue continuum (similar to a late A, early F type star) but with no obvious features above the noise. At this resolution and SNR (R~120 SNR ~27) a narrow emission line would need to be  fairly strong to be detected but the H alpha EW of 22 Angstrom quoted in the ATel would I think have been significantly above the noise. It appears likely therefore that the emission has faded.

The spectrum, with ~ 2 sigma uncertainties and a typical F2v spectrum (Pickles) overlaid is attached below

Robin

garypoyner's picture
Offline
Last seen: 12 hours 16 min ago
Joined: 04/03/2014 - 15:40
Re: HR Lyr

Thanks for posting this Robin.  It does indeed look like HR Lyr is on it's way up to it's normal  quiescence - which can be quite active by the way.  

So the emission lines fade whilst HR Lyr recovers.  What do you make of that?

Gary

Robin Leadbeater's picture
Offline
Last seen: 3 hours 37 min ago
Joined: 05/03/2014 - 00:50
HR Lyr emission lines

Hi Gary,

ATel 9418 makes the suggestion that the H alpha emission at least  may be present at times weakly even in the normal quiescent state and stays at the same absolute strength but becomes more obvious as the continuum drops (ie constant flux but increasing Equivalent Width relative to the continuum)  My spectrum is not really good enough to confirm this though.

I did also have a try with the ALPY at normal resolution (Thanks to the support from the Harold Rildley grant I now have the capability to switch resolution more easily) but the SNR at this magnitude is too poor to show any more than the general continuum shape. I wonder if the Asiago team are still keeping an eye on it with the 1.2m telescope?

Robin

Jeremy's picture
Offline
Last seen: 7 hours 25 min ago
Joined: 04/03/2014 - 22:00
HR Lyr

It's great to see your work on spectroscopy of HR Lyr, Robin. Well done!

The system is indeed on the rise again as Gary has mentioned. It's been C= 16.2-16.4 the last 3 nights.

It's remarkable that such little spectroscopy has been done on this old nova - and others.

Best regards,

Jeremy